Telephone for children

ABSTRACT

In order to be able to convert a fully functional telephone, in particular a mobile telephone, into a “child&#39;s telephone” without requiring a large degree of expenditure, it is provided that, if appropriate in addition to further keys, just one of more keys for dialing a telephone number are accessible on the telephone, which further keys cause a stored telephone number to be dialed when they are activated.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a telephone, particularly a mobiletelephone for use by children, which is designed such that only certainpreprogrammed keys for dialing a telephone number stored in anelectronic memory of the telephone are accessible to the child.

2. Description of the Prior Art

By providing their child with a known telephone, particularly a mobiletelephone, parents enable the child to establish, in an emergency, alink to an emergency call center, such as a rescue center or the police.In addition to establishing a link to an emergency call number or anoffice associated with the emergency call number, however, it is alsopossible in conventional mobile telephones to establish any otherdesired telephone links. Because this can entail considerable costs forthe parents, many parents refrain from making use of this facility whichis in itself desirable.

According to the current state of the art, there are various possibleways of enabling mobile telephones to make rapid emergency calls.

The American U.S. Pat. No. 5,365,570 A discloses, for example, a mobileterminal which is equipped for rapid emergency calls and which has aloudspeaker, microphone and a keypad which has an emergency call key fordialing the emergency call number 911 which is valid in the UnitedStates. When this emergency call key is activated, a link can be madequickly to the police, to the fire service or to a local rescue center.

A further American patent U.S. Pat. No. 4,802,210 A is concerned with asecurity device which can be used to prevent unauthorized access to someof the keys on the keypad of a mobile telephone. The security device iscomposed here of a plastic cover panel which is hooked onto one side ofthe key panel into a cutout provided for that purpose in the housing,and which can be locked on the opposite side of the key panel using asnap closure mechanism. The cover panel cannot be removed until after itis unlocked using a special key. The cover panel contains here twosquare-shaped openings which permit access to only two of the keys ofthe key panel.

Furthermore, according to the current state of the art further mobiletelephones are known which have cover devices for some of the keys onthe keypad of the mobile telephone. In European patent EP-0 414 365 A, amobile phone is described which is composed of two housing parts A and Bwhich can be inserted one into the other and which are held together bya helical spring. The housing part A contains a loudspeaker, a keypadTF1 for the keys of the dialing numerals and a keypad TF2 for additionalfunction keys, and housing part B contains a microphone. In the fullypulled-out state of the housing parts A and B of the mobile telephone, auser has complete access both to the keys of the keypad TF1 and to thekeys of the keypad TF2. In this case, all the functions of the mobiletelephone are completely available to him. In contrast, in the state inwhich the housing parts A and B of the mobile telephone are pushedtogether, the keys of the keypad TF1 are covered in order to preventunintentional, accidental incorrect activation of the keys as a resultof lack of attention by an adult user or as a result of access bychildren. In this case, activating the keys of the keypad TF2 provides auser with only a limited functional scope of the mobile telephone. Inthis state, the keypad TF1 is protected against serious damage which canoccur, for example, when the user inadvertently drops the mobiletelephone.

An object of the present invention, therefore, is to provide atelephone, in particular a mobile telephone, which is suitable forchildren, keeping the above concerns in mind

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a conventionaltelephone, such as a mobile telephone or a wireless telephone, designedin such a way that just one or more preprogrammed keys for dialing atelephone number stored in an electronic memory of the telephone areaccessible. In order to achieve this, the conventional mobile telephoneis provided with a cover which covers all the keys and via which anydesired non-preprogrammed telephone link can be established. This willrelate, in particular, to the numerical keys, but is not restricted tothis depending on the mobile telephone.

In order to bring about the desired function on a known mobiletelephone, there is provision for the parents or a service center topreprogram the keys which are not covered by the cover with onetelephone number in each case. The telephone number which is input whenthe keys are assigned and which can be dialed by activating therespective key is stored in the electronic memory of the mobiletelephone. One of the keys which is still accessible after the cover ismounted is preferably pre-assigned to an emergency call number, such as110, 112 etc. After the pre-assignment of the keys has been performed inthe fashion described, the cover is detachably fastened to the keypad ofthe mobile telephone. For this reason, the cover then permits accessonly to such keys with which either no telephone link can be establishedor merely a telephone link can be established to a preprogrammed orpredetermined telephone number; for example, an emergency call center,the mobile telephone number of the mother or the father, and so on.

The cover is preferably fastened on the upper side of the housing insuch a way that the cover can be removed again only with a special tool.The special tool can be, for example, a key via which a child protectionwhich is inserted into a socket can be pulled out. The “beard” of thekey is inserted into a (slot-shaped) opening in the cover as in the caseof the child protection, and turned slightly. Pulling arms on the beardthen engage behind the cover so that the latter can be pulled off from aclamping arrangement on the housing of the telephone. If the cover isfastened to the upper side of the housing of the telephone by, forexample, screws, they may be, for example, screws which do not have aslot but are rather provided with two blind holes which are provided tothe left and right of the center of the screw head. The correspondingscrewdriver or some other special tool and the cover can then beincluded, for example, with a telephone which permits the abovementioned functions. In this way, the parents can also easily “convert”a corresponding telephone into a “child's telephone” with an emergencycall function.

In an alternative and/or additional solution there is provision for thetelephone of the present invention to have a link-establishing devicewhich establishes a telephone link with a telephone number stored in thememory of the telephone if a key assigned to the stored telephone numberis activated.

In order to bring about this function, the link-establishing device canbe activated or deactivated via the correct entry of a PIN (PersonalIdentification Number). In order, therefore, to be able to convert, forexample, a fully functional mobile telephone into a child's mobiletelephone, the corresponding menu item of the operating software of themobile telephone is selected. The software requests the currently activePIN which is input, for example, by one of the parents, compares theentered PIN with a stored PIN and, if both correspond, activates thelink-establishing device so that the latter prevents a telephone linkbeing established to a subscriber of a telephone number which is notauthorized. Before or after this procedure, the software preferablyrequests the telephone numbers which are assigned to the correspondingkeys of the mobile telephone; these being, for examples the mobiletelephone number of the mother and so on. This restriction of thefunctionality of the mobile telephone to its use as a child's mobiletelephone can then be cancelled, for example, and the mobile telephonecan be converted to its normal functionality by one of the parentsinputting the correct PIN. For this purpose, a corresponding menu itemis preferably provided in the operating software of the mobiletelephone.

In one preferred embodiment of the present invention, there is provisionthat when the “child's mobile phone mode of operation” is activated onekey of the mobile telephone is automatically assigned an emergency callnumber, such as 110, 112 or some other suitable emergency call number inthe operating zone of the mobile telephone, by the operating software ofthe mobile telephone. In another exemplary embodiment, this assignmentcan alternatively or additionally be brought about by virtue of the factthat the mobile telephone is provided with an electrical contact whichis closed by the cover being slid on or pressed on or the like onto theupper part of the housing.

In order to prevent any desired telephone number being able to bedialed, a cover according to the present invention covers at least allthe keys of the telephone via which a single number can be dialed, inparticular insofar as this is not already prevented by the linkestablishing device. Apart from this aspect, it also may be appropriateto provide a telephone which is functional per se with a cover accordingto the present invention in order to make the telephone easier to use.This is achieved in that a selection of the accessible keys of thetelephone is made via the cover and all or a portion of the keys of thetelephone which are made accessible by the cover is assigned topre-programmed telephone numbers.

In a more preferred embodiment of the present invention, there isprovision that the cover covers the emergency call key with apredetermined breakage or predetermined bending region so that the keycannot be activated until the region has been destroyed or bent, whichis easy to bring about.

Likewise, there may be a provision that the cover is formed integrallyonto the upper shell of the housing of the mobile telephone. Acorresponding upper shell of the housing can then be included with themobile telephone, for example, when it is sold, so that thecorresponding upper shell of the housing can be replaced (as easily aspossible via appropriate measures) with the already pre-mounted uppershell of the housing without a cover. This can take place, for example,at the place where the customer acquires its mobile telephone.Furthermore, it is conceivable for an appropriate upper shell of thehousing to be available with a cover as an accessory. In anotherexemplary embodiment of the present invention, there is provision forthe mobile telephone to be supplied with an upper shell of the housingwhich already has a corresponding cover.

In a further exemplary embodiment of the present invention there isprovision that the cover is designed in such a way that lettering cardscan be mounted on the cover next to non-covered keys for dialing apre-assigned telephone number or the like. These lettering cards thenindicate to the child or another person the function of the adjacent,accessible key of the mobile telephone. The function of the respectivekey can be indicated via the adjacent lettering card or the like via asuitable text or even via pictograms or the like. Standard letteringcards are preferably included with the mobile telephone.

Of course, the measures according to the present invention not onlyapply to a mobile telephone, such as what is referred to as a mobilephone, for making telephone calls in one or more mobile radio networksor for a wireless telephone for operating in the vicinity of a basestation assigned to the wireless telephone, but also apply to awire-bound telephone for operating on a telephone socket.

In summary, corresponding operating software or the like and/or acorresponding cover in a mobile telephone in which individual keys canbe pre-assigned to a telephone number therefore permits a simple andcost-effective conversion of a telephone which has unrestrictedfunctional capability, such as in particular a mobile telephone, into achild's mobile phone or child's telephone in which the child or anotherperson requiring help is enabled to establish a telephone link to anemergency call center or to predetermined telephone subscribers. Thisconversion of an initially completely functional telephone into atelephone with restricted functional capability can be easily reversedagain by the measures according to the present invention. Of course, theaforementioned functions, which are made possible by the software of thetelephone, a also can be implemented by suitable hardware or byinputting specific key combinations.

Until now the point has been made that telephones or covers according tothe present invention can be used by children. Of course, the use of thetelephones or covers according to the present invention is notrestricted to this group of persons. The telephones and covers accordingto the present invention are suitable not only for children but also,for example, for persons with health risks, elderly people and evenpersons engaged in hazardous sports.

Additional features and advantages of the present invention aredescribed in, and will be apparent from, the Detailed Description of thePreferred Embodiments and the Drawings.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a known mobile telephone with full functional capability;

FIG. 2 shows the mobile telephone from FIG. 1 onto which a first coverhas been fitted in the vicinity of the keypad in order to restrict thefunctionality of the mobile telephone;

FIG. 3 shows the mobile telephone from FIG. 1 onto which a second overhas been fitted in order to restrict the functionality;

FIG. 4 shows the mobile telephone from FIG. 2 with the first cover incross section along the sectional line A-B in which the electroniccomponents of the mobile telephone are not illustrated;

FIG. 5 shows the mobile telephone from FIG. 3 with the second cover incross section along the sectional line C-D in which the electroniccomponents of the mobile telephone have been omitted; and

FIG. 6 shows the mobile telephone from FIG. 1 with a third cover in thevicinity of the keypad.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The known mobile telephone 1 according FIG. 1 has, in particular, aloudspeaker 2, a display 3, a microphone 4, a keypad 5, a first cursortoggle switch 6, a second cursor toggle switch 7, a telephone directorykey 8, an on hook key 9, an off hook key 10 and an antenna 11.

In order to establish a particular desired telephone link, the off hookkey 10 is activated, and then the numerical keys are activated in thecustomary fashion in order to dial a telephone number. Alternatively, inthe mobile telephone with full functional capability (illustrated inFIG. 1) it is also possible to establish a telephone link by pressingthe telephone directory key 8, selecting an entry in the telephonedirectory of the mobile telephone using the first and/or second cursortoggle switch 6, 7 and subsequently dialing the telephone number afteractivating a confirmation key 17. In order to terminate the telephonelink, the user of the mobile telephone 1 presses the on hook key 9.

If the user of the mobile telephone 1 wishes to restrict thefunctionality of the mobile telephone, in particular in order to make itavailable to a child or a person requiring help, the user selects anappropriate menu item (not illustrated) of the operating software(Firmware) of the mobile telephone; for example, using the toggleswitches 6 and 7. The software of the mobile telephone requests, via thedisplay 3, the PIN (Personal Identification Number) of the user. Theuser enters his PIN via the numerical field (not yet covered) and thesoftware of the mobile telephone checks whether the PIN entered by theuser of the mobile telephone corresponds to the PIN provided in themobile telephone for activating the “child's mobile phone function”.This PIN is preferably the same PIN which the user must enter in orderto make his mobile telephone operational.

After a comparator in the electronics system (not illustrated) of themobile telephone has determined that the user is authorized to activatethe child's mobile phone function, the software of the mobile telephoneinquires which telephone numbers are to be assigned to the keys whichare made available in the “child's mobile phone mode of operation”.

Likewise, the software operating system of the mobile telephone 1indicates that an emergency call number, such as the telephone number 10if the mobile telephone is sold and marketed in Germany, is alreadyassigned to the emergency call key 13 in the “child's mobile phone modeof operation” by the Firmware. This can, if necessary, be adapted to thelocal conditions by the user. After the first programmable numerical key14, the second programmable numerical key 15 and the third programmablenumerical key 16 (cf. FIG. 2) are pre-assigned by the inputting of thetelephone numbers assigned to the keys, the user confirms thecorrectness of the inputs and activates the child's mobile phone mode ofoperation. When the child's mobile phone mode of operation is activated,a link-establishing device (not illustrated) in the electronic system ofthe mobile telephone 1 prevents a telephone link being established to atelephone number which differs from the telephone numbers which areassigned to the programmable numerical keys 14, 15 and 16 and stored ina memory (not illustrated) of the mobile telephone 1. Likewise thelink-establishing device according to the present invention prevents atelephone link being established to a telephone number which is storedin the telephone directory of the mobile telephone 1 and which is notauthorized for dialing.

The cover 30 illustrated in FIG. 2 is subsequently fitted onto themobile telephone 1 and covers the non-preprogrammed keys in the child'smobile phone mode of operation. The cover 30 surrounds the keypad 5 andthe left-hand and the right-hand lateral surfaces 31 and 32 of thetelephone 1 and then extends on over the lateral surfaces to theunderside of the telephone 1, as is clear in particular from FIG. 4. Inthe vicinity of the left-hand and right-hand underside of the housing ofthe telephone 1, the cover 30 is bent upward at each of its lateralsurfaces and forms a left-hand guide rail 35 and a right-hand guide rail36, as is clear in FIG. 4 from the sectional view along the sectionalline A-B in FIG. 2. The underside of the housing of the telephone 1 has,in the vicinity of the left-hand lateral surface 31 and of theright-hand lateral surface 32, a left-hand guide groove 33 and aright-hand guide groove 34 which extend along the left-hand andright-hand lateral surfaces 31 and 32. The left-hand guide groove 33 andthe right-hand guide groove 34 preferably start at the lower end of thetelephone 1. When the cover 30 is mounted, it is fitted onto the mobiletelephone from below, i.e. from the microphone side, the left-hand guiderail 35 sliding in the left-hand guide groove 33, and the right-handguide rail 36 sliding in the right-hand guide groove 34. The cover 30 isthen fitted onto the mobile telephone until the cover 30 exposes thepreprogrammed numerical keys 13, 14, 15, 16 in its final position andcovers all the other numerical keys. The guide grooves 33 and 34 and theguide rails 35 and 36 are preferably matched to one another in theirdimensions in such a way that the respective rear end of the guidegroove 33 or 34 forms, in this final position, a stop for the left-handguide rail 35 and the right-hand guide rail 36.

In the final position, a projection or the like which is respectivelyprovided on the right-hand and left-hand guide rail 35, 36 latches intoa complementarily shaped recess in the guide groove 33 and 34. In orderto release the cover, it is then necessary to use a screwdriver, forexample.

The cover 40 illustrated in FIG. 3 differs from the cover 30 illustratedin FIG. 2 in that a left-hand guide groove 43 is provided in theleft-hand lateral surface 31, and a right-hand guide groove 44 isprovided in the right-hand lateral surface 32 of the telephone 1. In thefitted-on state, the left-hand guide rail 45 of the cover 40 lies in theleft-hand guide groove 43, and the right-hand guide rail 46 lies in theright-hand guide groove 44 of the telephone 1, as is clear in particularfrom FIG. 5. The cover 40 is fitted on in the same way as the cover 30is fitted on. Likewise, the left-hand guide groove 43 and the right-handguide groove 44 can also form a stop for the cover 40 when the latterreaches its final position after being fitted onto the telephone 1.

In order to fasten the cover on the upper side of the housing of themobile telephone 1 it is possible, for example, also to provide a clamparrangement or a latch device in the vicinity of the keypad 5.

An example of a possible latch device is described below in more detail.The mobile telephone 1 has a countersunk keypad 5. In the vicinity ofthe cover 12 (illustrated in FIG. 6), and the three edge regions of thekeypad 5 adjoining the cover 12, cutouts (not illustrated) through whichspring-back mounts 18, 19, 20, 21 and 22 engage are provided, thecut-outs holding the cover 12 on the keypad 5 of the mobile telephone 1.For the sake of clarity, the spring-back mounts 18, 19, 20, 21 and 22have been illustrated in FIG. 6. In the specific embodiment of thepresent invention, the spring-back mounts are bent under the edgeregions of the keypad 5.

In order to prevent the cover 12 lifting off slightly from the keypad 5,which is undesirable, it is possible to provide a conical screw, whichpenetrates the upper side of the housing from above, between therespective two spring-back limbs of the spring-back mounts 18, 19, 20,21 and 22, the screw being screwed into the upper side of the housingand subsequently pressing the spring-back limbs of the respectivespring-back mount apart so that the spring-back limbs cannot be pulledout of the cutouts in the edge regions of the keypad 5. In order toprevent unauthorized removal of the screws and subsequently of the cover12, the latter preferably have, instead of a slot, two or more blindholes which are provided off center in the screw head. A correspondingscrew can then only be unscrewed with a special screwdriver which isadapted to this screw. Of course, the latch device can also be designedin some other way if another special tool is to be used to release thecover. For example, it also could be possible to lift off the cover fromthe keypad 5 from a clamping arrangement of the cover to the elevatededge regions of the keypad 5 using a special key, as in the case of achild safety plug.

Such a way of securing the cover 12, 30, 40 on the keypad 5 which isbrought about via the described special screws or the like preferablywill be provided only if the mobile telephone does not have thelink-establishing device (not illustrated) which prevents the use of thenumerical keys located under the cover by software or hardware means.

The cover 12, 30, 40 preferably has, next to the pre-assignedprogrammable numerical keys 14, 15 and 16 and next to the emergency callkey 13 respectively, lettering (not illustrated) which indicates thefunction of the respective key. For this purpose, the lettering fieldscan be provided with lettering cards, for example.

The cover 12, 30, 40 which is provided with cutouts in the vicinity ofthe programmable numerical keys 14, 15, 16 and the emergency call key 13preferably has, in the vicinity of the emergency call key 13, aprotective cover (not illustrated) for protecting against unintentionalactivation of the emergency call key 13. The protective cover may be,for example, a predetermined breakage or predetermined bending region ofthe cover so that the protective cover can be destroyed relativelyeasily or can be bent in order to activate the emergency call key 13. Ofcourse, some other suitable measure for protecting against incorrectactivations may also be provided.

Although the present invention has been described with reference tospecific embodiments, those of skill in the art will recognize thatchances may be made thereto without departing from the spirit and scopeof the invention as set forth in the hereafter appended claims.

What is claimed is:
 1. A telephone, comprising: a loudspeaker; amicrophone; an electronic memory; at least one keypad having at leastone programmable key, wherein a telephone number which is bothassociated with the programmable key and stored in the electronic memoryis dialed upon actuation of the at least one programmable key; a covercovering keys of the at least one keypad except for at least one key ofthe at least one programmable key; and software providing first andsecond operating modes of the telephone user selectable by use of asecurity code, the second operating mode having reduced functionalityrelative to the first operating mode, wherein when the telephone is inthe second reduced functionality mode, a substantial number of the keyscovered by the cover are electronically inoperable and the at least onekey not covered by the cover is electronically operable.
 2. A telephoneas claimed in claim 1, further comprising: a link-establishing devicewhich sets up a telephone link with the telephone number which is bothassociated with the at least one programmable key and stored in theelectronic memory.
 3. A telephone as claimed in claim 1, wherein thetelephone number is an emergency call number.
 4. A telephone as claimedin claim 1, wherein all keys of the telephone for dialing a single digitare covered with the cover.
 5. A telephone as claimed in claim 4,further comprising: a displaceable part on the cover which covers aprogrammable key associated with an emergency call number, wherein theprogrammable key may be actuated after at least one of breaking andbending the displaceable part, the displaceable part simultaneouslyprotecting against inadvertent actuation of the programmable key.
 6. Atelephone as claimed in claim 4, wherein the cover is detachably mountedon an upper part of a housing of the telephone.
 7. A telephone asclaimed in claim 6, wherein the cover can be detached from the upperpart of the housing via one special tool.
 8. A telephone as claimed inclaim 4, wherein the cover is integrally formed with an upper part of ahousing of the telephone.
 9. A telephone as claimed in claim 4, furthercomprising: lettering on the cover which explains functions ofprogrammable keys made accessible by the cover.
 10. A telephone isclaimed in claim 4, wherein upon mounting the cover to the telephone,the cover activates an electronic contact on the telephone which causesan activation device of the telephone to assign a predeterminedemergency call number to one of the keys of the telephone not covered bythe cover, and the link-establishing device of the telephoneautomatically establishes the link to the emergency call number afterthe respective key has been actuated.
 11. A telephone as claimed inclaim 4, wherein the cover includes a left-hand guide rail and aright-hand guide jail, the cover surrounding the keypad and left-handand right-hand lateral surfaces of the telephone, the left-hand guiderail located in a left-hand guide groove on a left-hand underside of thehousing and the right-hand guide rail located in a right-hand guidegroove on a right-hand underside of the housing.
 12. A telephone asclaimed in claim 4, wherein the cover includes a left-hand guide railand a right-hand guide rail, the cover surrounding the keypad and partof left-hand and right-band lateral surfaces of the telephone, theleft-hand guide rail located in a left-hand guide groove on theleft-hand lateral surface and the right-band guide rail located in aright-hand guide groove on the right-hand lateral surface.
 13. Atelephone as claimed in claim 11, wherein the left-hand and right-handguide rails each have a projection which engages a depression in therespective left-hand and right-hand guide groove associated therewith.14. A telephone as claimed in claim 1, wherein the telephone is a mobiletelephone capable of linking telephone calls in at least one mobileradio network.
 15. A telephone as claimed in claim 1, wherein thetelephone is a wireless telephone for operating in a vicinity of a basestation assigned to the wireless telephone.
 16. A telephone as claimedin claim 1, wherein the telephone is a wire-bound telephone foroperating on a telephone socket.